i have MANY questions about my new iphone?

[Tiffany]

i just the iphone 4s (not 5) cause there's no difference but anyway i have a lot of questions. i have 2gb data plan.

1) i put in music in my phone from my computer but does it cost a lot of money/raise data charges if i listen to a lot of music?
2) if i watch 10 high quality youtube videos everyday does it raise the data?
3) if i put in videos in my itunes and convert it into my iphone, will it cost money. (i watch A LOT of videos)
4) i have a lot of apps but i downloaded all of them for free but which ones raise data???
Social: tumblr, kakaotalk, facebook
Games: Ninja jump, unblock me, jetpack, subway surf, anipang, boys in arms 2
Photography: photo mage, pic stitch, camwow, camwowpro, instagram, camera!, PE-Fotlr
Starbucks, Emoji, LyricFind Lite
Youtube, SAR QOTD, SAT VOCAB


Do any of those apps raise data charges?? ^ I play a lot of games also btu will that raise the data/bill?

Last QUESTION: i have a 2GB data plan but is it "the more data you use, the higher the bill?" or do they charge you do the same if you use 1 GB and 1.7 GB?